Assessment of Ambient Air Quality Around Cement Plants in Ewekoro, Ogun State, South West Nigeria

Cement manufacturing is a major source of particulate matter and gaseous pollutants, and communities located near cement plants frequently experience elevated levels of airborne dust and respiratory health impacts. This study assessed ambient air quality around a major cement plant in Ewekoro, Ogun State, South West Nigeria, and examined its association with respiratory health among nearby residents. Particulate matter (PM10 and PM2.5), sulfur dioxide, and nitrogen dioxide were measured at five monitoring stations at distances ranging from 500 metres to three kilometres from the plant boundary. A cross-sectional survey was administered to 420 residents across four communities. Clinic records from local health facilities were reviewed for respiratory illness trends over a three-year period. Findings showed that PM10 concentrations at the 500-metre monitoring station averaged 128 micrograms per cubic metre, exceeding the WHO annual guideline of 20 micrograms per cubic metre. Concentrations declined with increasing distance but remained above guideline values at two kilometres. Respiratory symptom prevalence was highest among communities within one kilometre of the plant. Spirometric testing conducted on a sub-sample of 100 residents revealed obstructive lung function in twenty-nine percent of participants. The study recommends continuous stack emission monitoring, mandatory construction and maintenance of effective dust suppression systems, and community health monitoring programs for populations near cement production facilities. Keywords: cement plant, air quality, particulate matter, Ewekoro, respiratory health.